British Prime Minister Theresa May became emotional as she announced that she will step down as the leader of the Conservative Party.Toby Melville / Reuters

British Prime Minister Theresa May announced Friday that she “will shortly leave the job that has been the honor of my life to hold.”

The long-anticipated address, outside Downing Street, confirms that May will step down as the leader of the Conservative Party on June 7. She will remain prime minister until the party chooses a new leader, a process that will take approximately six weeks.

In many ways, May’s announcement marks a solemn end to a profoundly weak yet surprisingly stable premiership. But if the past three turbulent years of parliamentary deadlock, infighting, and division have demonstrated anything, it’s that May’s leadership ended a long time ago.

Her premiership didn’t begin that way. When May succeeded David Cameron as prime minister in July 2016, she inherited a parliamentary majority and a 20-point lead in the polls over the opposition Labour Party. She was dubbed the “New Iron Lady,” in a favorable nod to the country’s only other female prime minister, Margaret Thatcher. But she also inherited a policy challenge of historic proportions: to deliver on a referendum result she didn’t support, and take Britain out of the European Union.

Whatever strength she had at the start of her premiership, she quickly lost. First, May made the consequential decision on March 29, 2017, to trigger Article 50, the EU’s time-limited exit procedure, thereby setting into motion a two-year countdown for the country’s departure. Less than a month later, in a profound miscalculation, she announced a snap general election in a bid to increase a parliamentary majority that she would ultimately come to lose. By the time negotiations with the EU formally kicked off in Brussels in July, May lacked a governing majority and, crucially, a plan. Time had already started running out.

The ill-fated call for a snap election was the beginning of the end for May. Still, she persisted—first by striving to reach a negotiated deal on the terms of Britain’s withdrawal from the EU, and once more by attempting to rally enough parliamentary support behind it. If there were questions about whether the agreement had any support among members of her own party, they were soon dispelled: It did not.

Throughout it all, there were many false starts to the end of the May era. Many, many false starts. But in the end, it wasn’t the 36 cabinet resignations, the Tory infighting, or the multiple challenges to her leadership that spelled the end for this British prime minister. Rather, it was her thrice-defeated Brexit deal and her bid this week to bring it back for a fourth and final vote in Parliament.

Paradoxically, it was May’s unpopular deal with the EU that has enabled her to last this long. When the prime minister offered assurances to her Conservative Party colleagues in December that she wouldn’t lead the party into the next general election, she did so in a twin bid to avoid a no-confidence vote in her leadership and salvage her negotiated agreement with the European Union outlining the terms of Britain’s withdrawal from the bloc. Three months later, she spelled out that aim even further by pledging to step down just as soon as members of Parliament passed her deal. When she presented lawmakers with “one last chance” to deliver on Brexit by backing a new, “compromise” agreement, it was clear there was no hope for her deal passing muster in Parliament—and no hope for her.

The race to succeed May is already well under way. Whoever replaces her will undoubtedly face the same parliamentary deadlock and division that she did—and will likely face the same challenge of delivering Brexit. “He or she will have to find consensus in Parliament where I have not,” May said, calling on her successor to reach a compromise that she was ultimately never able to deliver.

“She’ll be [remembered as] the prime minister that failed to deliver Brexit,” Anand Menon, the director of the London-based research institute UK in a Changing Europe, told me. “And that was the only thing that she tried to do.”

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